fix(s6): register profile gateways without auto-starting (#46266)

* fix(s6): prevent profile create from auto-starting gateway service

When hermes profile create runs inside an s6 container,
_maybe_register_gateway_service() calls register_profile_gateway()
which creates the service directory and triggers s6-svscanctl -a.
Previously the service always started immediately, causing profiles
that share the main gateway's bot token (e.g. Kanban worker profiles)
to fail with a token-lock conflict and persist gateway_state: running
— becoming zombies that resurrect on every container restart.

Wire the existing start_now parameter through the S6 implementation:
when start_now=False, write a  marker file (same pattern as
container_boot.py _register_gateway_slot) so s6-supervise leaves the
service stopped until the user explicitly runs hermes -p <profile>
gateway start.

4 files, +61/-6, 4 new tests (all passing).

* test(docker): wait for gateway running state before restart

---------

Co-authored-by: liuhao1024 <sunsky.lau@gmail.com>

hermes_cli/profiles.py

@@ -1268,7 +1268,7 @@ def _maybe_register_gateway_service(profile_name: str) -> None:
     if not mgr.supports_runtime_registration():
         return  # host backend; no-op
     try:
-        mgr.register_profile_gateway(profile_name)
+        mgr.register_profile_gateway(profile_name, start_now=False)
     except ValueError:
         # Already registered (e.g. the container-boot reconciler ran
         # first and brought up a stale slot). That's fine.